Cho H.J.,Korea University |
Lee H.-S.,Korea University |
Jung E.Y.,Korea University |
Park S.Y.,Kongju National University |
And 5 more authors.
Journal of the Korean Society of Food Science and Nutrition | Year: 2010
Silk sericin protein was hydrolyzed by seven proteolytic enzymes to examine the effectiveness of the hydrolysates to bind iron. The amino acid nitrogen contents of hydrolysates by Flavourzyme were higher than the others enzymes, and its iron binding capacity showed dose-dependent increase. The bioavailability of iron binding peptide from sericin hydolysates was investigated in iron-deficient rats. Three-week-old male rats were fed iron-deficient diet for three weeks. Rats were divided into four groups (DD: no treated group on iron deficient diet, DD+HI: heme-iron treated group, DD+OI: sericin-Fe, and DD+II: inorganic iron (FeSO4) treated group, and then iron supplemented by injection for one week. After oral administration for one week, the iron contents of serum and liver were significantly higher in DD+OI (4.2 μg/mL and 80.1 μg/mL) and DD+HI (3.2 μg/mL and 70.6 μg/mL) than DD (2.0 μg/mL and 47.9 μg/mL). Hemoglobin content of treated groups was significantly higher than DD, but the significant difference among groups was not shown. Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels did not show any significant difference among all groups. Binding iron to peptide from sericin hydolysates seems to improve its bioavailability and to hasten the cure of iron deficiency in experimental rat.
Lee S.H.,Chungbuk National University |
Park D.,Chungbuk National University |
Yang G.,Chungbuk National University |
Bae D.-K.,Chungbuk National University |
And 10 more authors.
European Journal of Nutrition | Year: 2012
Purpose: The objective was to confirm the anti-obesity activity of a silk peptide (SP) and a silkworm pupa peptide (SPP) in rats fed a high-fat diet (HFD) and to elucidate their action mechanism(s) in a preadipocyte culture system. Methods: In an in vitro mechanistic study, the differentiation and maturation of 3T3-L1 preadipocytes were stimulated with insulin (5 μg/mL), and effects of SP and SPP on the adipogenesis of mature adipocytes were assessed. In an in vivo anti-obesity study, male C57BL/6 mice were fed an HFD containing SP or SPP (0.3, 1.0, or 3.0%) for 8 weeks, and blood and tissue parameters of obesity were analyzed. Results: Hormonal stimulation of preadipocytes led to a 50-70% increase in adipogenesis. Polymerase chain reaction andWestern blot analyses revealed increases in adipogenesisspecific genes (leptin and Acrp30) and proteins (peroxisome proliferator-activated receptor-c and Acrp30). The hormoneinduced adipogenesis and activated gene expression was substantially inhibited by treatment with SP and SPP (1-50 μg/mL). The HFD markedly increased body weight gain by increasing the weight of epididymal and mesenteric fat.Body and fatweightswere significantly reduced by SP and SPP, in which decreases in the area of abdominal adipose tissue and the size of epididymal adipocytes were confirmed by magnetic resonance imaging and microscopic examination, respectively. Long-term HFD caused hepatic lipid accumulation and increased blood triglycerides and cholesterol, in addition to their regulatory factors Acrp30 and leptin. However, SP and SPP recovered the concentrations ofAcrp30 and leptin, and attenuated steatosis. Conclusions: SP and SPP inhibit the differentiation of preadipocytes and adipogenesis by modulating signal transduction pathways and improve HFD-induced obesity by reducing lipid accumulation and the size of adipocytes. © Springer-Verlag 2011.
Kim T.K.,Chungbuk National University |
Park D.,Chungbuk National University |
Lee S.H.,Chungbuk National University |
Choi Y.J.,Chungbuk National University |
And 11 more authors.
Food Science and Biotechnology | Year: 2011
Physical function-improving effects of a silk amino acid preparation (SAA) in Parkinson's disease (PD) model rats were investigated. 6-Hydroxydopamine (6-OHDA, 8 μg)+ascorbic acid (0.6 μg) was injected into right medial forebrain bundle of 8-week-old Sprague-Dawley rats to induce PD, and SAA (50, 160, or 500 mg/kg) was orally administered for 30 days. On day 15 and 30, behavioral abnormalities, neuronal loss, and dopamine and its metabolites were analyzed. Injection of 6-OHDA impaired pole test performances, which were markedly improved by treatment with SAA. Increased using rate of ipsilateral (normal) forelimb in cyclinder test and apomorphine (0.05 mg/kg)-induced circling behavior of PD rats were remarkably corrected by the compounds. In addition, 6-OHDAinduced loss of neurons as well as decreases in dopamine and its metabolites were significantly attenuated by SAA. The results indicate that SAA preserves movement function of PD model animals by protecting dopamine neurons against 6-OHDA neurotoxicity. © KoSFoST and Springer 2011.
PubMed | Worldway Co., Chungbuk National University and Gangneung - Wonju National University
Type: | Journal: Toxicology and applied pharmacology | Year: 2016
This study investigated the effects of a silk peptide fraction obtained by incubating silk proteins with Protease N and Neutrase (SP-NN) on cognitive dysfunction of Alzheimer disease model rats. In order to elucidate underlying mechanisms, the effect of SP-NN on the expression of choline acetyltransferase (ChAT) mRNA was assessed in F3.ChAT neural stem cells and Neuro2a neuroblastoma cells; active amino acid sequence was identified using HPLC-MS. The expression of ChAT mRNA in F3.ChAT cells increased by 3.79-fold of the control level by treatment with SP-NN fraction. The active peptide in SP-NN was identified as tyrosine-glycine with 238.1 of molecular weight. Male rats were orally administered with SP-NN (50 or 300mg/kg) and challenged with a cholinotoxin AF64A. As a result of brain injury and decreased brain acetylcholine level, AF64A induced astrocytic activation, resulting in impairment of learning and memory function. Treatment with SP-NN exerted recovering activities on acetylcholine depletion and brain injury, as well as cognitive deficit induced by AF64A. The results indicate that, in addition to a neuroprotective activity, the SP-NN preparation restores cognitive function of Alzheimer disease model rats by increasing the release of acetylcholine.
Han Z.-Z.,Research South, Inc. |
Koo K.-H.,Research South, Inc. |
Kim K.-H.,Research South, Inc. |
Bae J.-S.,Research South, Inc. |
And 13 more authors.
Food and Chemical Toxicology | Year: 2011
Acute and 90-day subchronic oral toxicity studies of Silk peptide E5K6 were performed in Sprague-Dawley rats. In the acute toxicity study, Silk peptide E5K6 was administered orally to male and female rats at a single dose of 2000 and 5000. mg/kg. Mortality, clinical signs and body weight changes were monitored for 14. days. There were no treatment-related changes in these parameters. Therefore, the Approximate Lethal Dose (ALD) of Silk peptide E5K6 in male and female rats is higher than 5000. mg/kg. In the subchronic toxicity study, Silk peptide E5K6 was administered orally to male and female rats for 90. days at a single dose of 500, 1000, and 2000. mg/kg. There were no toxicologically significant changes in clinical signs, body weight, food and water consumptions, ophthalmoscopic examination, urinalysis, hematological and serum biochemical examinations, necropsy findings, organ weights and histopathological examination of all of the animals treated with Silk peptide E5K6. These results suggest that the oral No Observed Adverse-Effect Level (NOAEL) of Silk peptide E5K6 is greater than 2000. mg/kg/day in both sexes and the target organs were not established. © 2011.
World Way Co. | Date: 2013-02-26
Nutritional food supplements not for medical purposes, containing peptide extracted from silk cocoon included in this class; nutritional food supplements not for medical purposes, containing tyrosine extracted from silk cocoon included in this class; nutritional food supplements not for medical purposes, containing silk sericin peptide extracted from silk cocoon included in this class.
Worldway Co. | Date: 2011-08-30
Nutritional food supplements containing silk cocoon components.